Understanding diel-vertical feeding migrations in zooplankton using bulk carbon and nitrogen stable isotopes

Abstract

We used bulk stable isotope analysis (SIA) to examine diel feeding activity in two vertically migrating krill species, Thysanoessa gregaria and Euphausia similis, off eastern Australia. SIA indicated feeding by both species above the thermocline at night, potentially on both particulate organic matter and microzooplankton. Our results support the use of SIA to investigate vertical migration and feeding in zooplankton. © 2014 The Author. Published by Oxford University Press. All rights reserved.